In Gear - Today's Trucking

So here we are in a new year and facing the reality
of yet another new engine era. Order a medium or
heavy truck now and it’s going to come with a
new variation on the emissions theme, thanks to
the U.S. Environmental Protection Agency.
There’s really nothing new to report on the SCR vs. EGR front,
however, aside from a couple of lawsuits. Interesting, but not
germane to your information needs.
Otherwise, both camps seem to have
hunkered down in nervous anticipation
of what the market—namely
you—will do in the next months and
years. The truth is, having enjoyed a
bit of a pre-buy in the last quarter of
2009 that saw them building trucks
at capacity, truck makers are now
expecting a ‘no-buy’ period through
at least the first quarter of this
new year.
And in all the blather and bluster about who has the best
answer to the 2010 challenge, nobody has really been telling you
much about what’s on offer in the way of power ratings and such.
Not all the engine-maker websites even include this fundamental
material, and if they do, it’s sometimes buried deep behind the
competitive stuff. So—painstakingly, I tell you—I’ve gathered all
that info in one place and created what ended up as a simple
spreadsheet to help you see what’s available for that moment
when—please—you decide to buy a truck or two.
First, a necessary review of what lead us here.
THE NEW REGIME
The new EPA regulations, by far the world’s most stringent emissions
rules, take us to almost zero allowable nitrogen oxides
(NOx) and particulate matter (PM) or soot. Specifically, 2010
engines can emit no more than 0.2 grams of NOx, which has been
phased in since the 2007 regs, and 0.01 grams of soot per brakehorsepower-hour,
unchanged from ’07. And for the first time
there’s a requirement for on-board diagnostics (OBD) on diesel
engines in highway vehicles grossing 14,000 lb and more.
These motors are as clean as you’ll ever see. Note that allowable
limits in 1998 were 4.0 grams of NOx and 0.1 grams of
particulate gunk. Which makes the improvement an almost
total conversion, at least in terms of those emissions (there are
others, of course).
It’s unclear what we’ll see next from the EPA.
THE NEW TECHNOLOGIES
Briefly, it’s well known that all engine manufacturers except
International will use a combination of SCR and cooled EGR. And
that includes Hino and Mitsubishi Fuso. In most cases, though
some lips are well sealed on such ’010 matters, this involves
slightly lower rates of EGR—meaning smaller air volumes are
2010 Engines
cooled and thrown back through the turbo than with ’07 EGR
motors. The addition of SCR aftertreatment means that less
emissions-busting has to take place in the combustion chamber.
It remains to be seen what this means in long-term practice but
in theory it’s a good thing, one likely result being the near elimination
of regenerations required in the DPF, or diesel particulate
filter. Volvo goes so far as to say its new engines won’t need regens
at all. And all SCR proponents claim fuel-economy improvements
compared to EGR-only diesels.
SCR systems demand the use of diesel exhaust fluid, or DEF,
residing in a frame-hung tank that will have to be replenished
about every second or third fuel
fill-up. The system sends a pre-
By and large we’ll avoid
the SCR vs. EGR debate
here and just give you the
hard-to-find basic specs.
cise amount of vapourized DEF
along with the hot exhaust
gases into a catalyst downstream
of the DPF. A chemical
reaction in there turns NOx into
clean nitrogen and water
vapour. DEF itself is not to be
feared, an American Petroleum
Institute certified product that’s
stable and harmless.
The upsides of the SCR-with-EGR answer are the dramatic
reduction in DPF regenerations and the promise—we’ll see—of
fuel-economy improvements. The downside is added weight,
some 250 to 350 lb, and the need to keep the DEF tank full. Plus a
surcharge of $10,000 or so.
International, of course, has opted for what it calls “advanced
EGR” and says the reason is that it’s simple and a known quantity.
It demands that much more air than before gets shovelled back
through twin turbochargers, so the air-management system
actually looks complicated. It remains to be seen what this does
to the number of DPF regenerations required. On the other hand,
there’s less weight added to the truck and there’s no DEF tank to
fill. You’ll see a hefty surcharge here too, though likely less than
with SCR.
Drivers of both systems report no issues with either one, and in
fact no change at all.
BY ROLF LOCKWOOD
MISCELLANEOUS NOTES
We’ll definitely see two all-new engines this year and possibly one
more. First is the Cummins ISX11.9 engine, a compact, inline-six
motor targeted at vocational trucks, day cabs, and emergency
vehicles. Originally developed for the Chinese market, it shares all
emissions componentry, including the common-rail XPI fuel
system and electronic controls, with its big brother the ISX15.
Ratings will likely go up to 425 hp and 1650 lb ft of torque, though
Cummins hasn’t released them yet. We won’t see it until about
mid-year.
Coming from PACCAR at some point this year—I’ve had it confirmed—will
be the compact 12.9-litre MX based on an engine
built from a clean-sheet design by the company’s European
subsidiary DAF in the Netherlands. A popular engine over there
(I’ve driven it and was impressed by its smoothness and quiet), it
was once to be built in a new plant in Mississippi. That plan has
JANUARY 2010 35